The saturation ageing tensile stiffness (SATS) test was developed in the UK in response to the deterioration in stiffness that had been observed on sites with high modulus base (HMB) materials. The test has been incorporated into the UK Specification for Highway Works and is now being adopted as a European test method for pavement durability. The available literature has been reviewed, together with the views of existing users, in order to understand the potential applicability and value of the test so as to help facilitate the decision as to whether the advantages from those uses warrant the adoption of this test in the Irish Specification for Road Works in the future. Tests undertaken on samples manufactured from a selection of Irish aggregates that covered the main aggregate types used in Ireland and the 15/25 pen bitumen specified in the test showed that all the mixtures complied with the bitumen content at its lower limit; two failed at the upper limit. Using more widely used 40/60 pen bitumen in the test reduced the SATS Durability Index significantly for the limestone aggregates but had little effect on others whilst using their own filler in the mixtures had little effect. Therefore, based on the SATS testing carried out in this study, there is little benefit from incorporating this test in its present form into the Irish Specification for Road Works when using native aggregate sources.

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